linux-kernel - Re: [PATCH] slimbus: Linux driver framework for SLIMbus.

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <74993ac9d11db0db7080c0864daef397.squirrel@www.codeaurora.org>
Date:	Mon, 4 Jun 2012 03:21:06 -0700 (PDT)
From:	"Sagar Dharia" <sdharia@...eaurora.org>
To:	"Sagar Dharia" <sdharia@...eaurora.org>, davidb@...eaurora.org,
	bryanh@...eaurora.org, kheitke@...eaurora.org,
	gclemson@...ience.com, broonie@...nsource.wolfsonmicro.com,
	linux-arm-msm@...r.kernel.org,
	linux-arm-kernel@...ts.infradead.org, rob@...dley.net,
	grant.likely@...retlab.ca, rob.herring@...xeda.com,
	ohad@...ery.com, gregkh@...uxfoundation.org,
	linus.walleij@...aro.org, rusty@...tcorp.com.au,
	joerg.roedel@....com, trenn@...e.de, ak@...ux.intel.com,
	linux-doc@...r.kernel.org, linux-kernel@...r.kernel.org,
	devicetree-discuss@...ts.ozlabs.org
Subject: Re: [PATCH] slimbus: Linux driver framework for SLIMbus.

> These are initial comments. A full review of the patch will take some
> time. While I am posting this email, this is the result of work both
> by myself, and my colleague Greg Clemson (cc'ed).
>
Thank you Marc and Greg for taking time to review this.

> The enumeration slim_ch_proto is incorrect. It declares 2 transport
> protocols which do not exist in the specification: SLIM_HARD_ISO;
> SLIM_AUTO_ISO.

The enums are more SW representation (and not 1-1 mapping). Difference
between HARD_ISO and AUTO_ISO with example:
Let's say the root frequency is 24.576MHz. then all 4K family channels
(sample rate multiple of 4K) can run isochronously, and all 11.025KHz
channel can run with good efficiency.
So if a client wants 11.025KHz and is does not want to do flow-control at
this root frequency, then the client can specify AUTO_ISO to get the next
available isochronous frequency.

> I suggest that term "enumeration address" should be used.
>
Thank you for catching this. I will change it where-ever applicable.

> b) Similarly to (a) the driver may be probed before the device has
> been given a logical address (LA). This makes sense in the case of
> driver that turns on the device (say via gpio) once the bus has
> booted. However, the driver then needs to sit and poll
> slim_get_logical_addr() until the logical address.
This is not the case anymore.
While taking care of the comments for RFC, I have introduced a completion
that will be signalled when LA is given to the device. The driver can wait
on that completion (wait_enum) instead of polling.

Regards
Sagar
Sent by an employee of the Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/